The battery in your Nokia 6230 (the BL-5C) has 850 mAh - this number is a measurement of talk time and standby time. With this, you are looking at right around 2 hours and 45 minutes of talk time and 43-44 hours of standby time. If you are not getting this, it may be a faulty battery. Bluetooth devices definitely drain battery life. One tip for charging your battery: Li-Ion batteries prefer frequent partial charges rather than being run all the way down and charged fully back up again - this should help your battery life.